Alternative Multi-dimensional Rappor

components/rappor/sampler_unittest.cc

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "components/rappor/sampler.h"
+
+#include "components/rappor/byte_vector_utils.h"
+#include "components/rappor/proto/rappor_metric.pb.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace rappor {
+
+const RapporParameters kTestRapporParameters = {
+    1 /* Num cohorts */,
+    1 /* Bloom filter size bytes */,
+    4 /* Bloom filter hash count */,
+    PROBABILITY_75 /* Fake data probability */,
+    PROBABILITY_50 /* Fake one probability */,
+    PROBABILITY_75 /* One coin probability */,
+    PROBABILITY_50 /* Zero coin probability */,
+    FINE_LEVEL /* Reporting level (not used) */};
+
+class TestSamplerFactory {
+ public:
+  static scoped_ptr<Sample> CreateSample() {
+    return scoped_ptr<Sample>(new Sample(0, kTestRapporParameters));
+  }
+};
+
+namespace internal {
+
+// Test that exporting deletes samples.
+TEST(RapporSamplerTest, TestExport) {
+  Sampler sampler;
+
+  scoped_ptr<Sample> sample1 = TestSamplerFactory::CreateSample();
+  sample1->SetStringField("Foo", "Junk");
+  sampler.AddSample("Metric1", sample1.Pass());
+
+  scoped_ptr<Sample> sample2 = TestSamplerFactory::CreateSample();
+  sample2->SetStringField("Foo", "Junk2");
+  sampler.AddSample("Metric1", sample2.Pass());
+
+  // Since the two samples were for one metric, we should randomly get one
+  // of the two.
+  RapporReports reports;
+  std::string secret = HmacByteVectorGenerator::GenerateEntropyInput();
+  sampler.ExportMetrics(secret, &reports);
+  EXPECT_EQ(1, reports.report_size());
+  EXPECT_EQ(1u, reports.report(0).bits().size());
+
+  // First export should clear the metric.
+  RapporReports reports2;
+  sampler.ExportMetrics(secret, &reports2);
+  EXPECT_EQ(0, reports2.report_size());
+}
+
+}  // namespace internal
+
+}  // namespace rappor